气候变化领域集成服务门户(CCPortal): Estimation and analysis of snow water equivalents based on C-band SAR data and field measurements

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DOI	10.1657/AAAR00C-13-135
	Estimation and analysis of snow water equivalents based on C-band SAR data and field measurements
	Sun, Shaobo; Che, Tao; Wang, Jian; Li, Hongyi; Hao, Xiaohua; Wang, Zengyan; Wang, Jie
发表日期	2015
ISSN	1523-0430
EISSN	1938-4246
起始页码	313
结束页码	326
卷号	47 期号:2
英文摘要	The spatial distribution of the snow water equivalent (SWE) of ground snow cover is one of the most important variables for understanding and simulating cold-region hydrological processes in high mountain areas. In this paper, the characteristics of C-band synthetic aperture radar (SAR) data in an area of shallow dry snow cover were analyzed based on microwave backscattering models and field snow cover measurements. The analysis revealed that the backscattering of shallow dry snow cover was dominated by the scattering of the snow-ground interface, and the dielectric constant and roughness parameters of the underlying frozen soil were the primary factors that affected the total scattering. The dielectric constant of the soil depended on the amount of liquid water present in the soil, and the amount of liquid water was primarily determined by the soil temperature. Furthermore, the insulation properties (thermal resistance) of the snow cover affected the underlying soil temperature. Consequently, the snow cover characteristics affected the backscattering signal recorded by the SAR sensors. Based on an investigation involving ENVISAT-ASAR data and simultaneous ground-based snow observations conducted on 14 March 2008, we found that the snow temperature decreased with increasing snow depth when the snow depth was less than 20 cm, and the temperature increased with decreasing snow depth when the snow depth exceeded 20 cm. Additionally, the amount of liquid water in the underlying frozen soil rapidly increased with increasing temperature. To estimate the SWE, we used a small number of field measurements data and SAR ratio images to develop two equations. The first equation defined the relationship between the snow's thermal resistance and backscattering ratio, and the second equation yielded the SWE from the estimated thermal resistance of the snow-covered area. The root mean square and relative errors of the estimated SWE were approximately 7.41 mm and 6.17%, respectively. The derived SWE also indicated that blowing snow and sun radiation were two primary factors that determined the spatial distribution of snow cover in mountainous areas.
WOS研究方向	Environmental Sciences & Ecology ; Physical Geography
WOS类目	Environmental Sciences ; Geography, Physical
WOS关键词	MICROWAVE DIELECTRIC BEHAVIOR ; EASTERN CANADA ; WET SOIL ; BACKSCATTER ; COVER ; DEPTH ; SCATTERING ; PARAMETERS ; SIGNATURES ; SURFACE
WOS记录号	WOS:000355627500012
来源期刊	ARCTIC ANTARCTIC AND ALPINE RESEARCH
来源机构	中国科学院西北生态环境资源研究院
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/241033
作者单位	[Sun, Shaobo; Che, Tao; Wang, Jian; Li, Hongyi; Hao, Xiaohua; Wang, Zengyan; Wang, Jie] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Heihe Remote Sensing Expt Res Stn, Key Lab Remote Sensing Gansu Prov, Lanzhou 730000, Peoples R China; [Che, Tao] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China; [Sun, Shaobo; Wang, Zengyan; Wang, Jie] Univ Chinese Acad Sci, Beijing 100049, Peoples R China; [Sun, Shaobo] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China
推荐引用方式 GB/T 7714	Sun, Shaobo,Che, Tao,Wang, Jian,et al. Estimation and analysis of snow water equivalents based on C-band SAR data and field measurements[J]. 中国科学院西北生态环境资源研究院,2015,47(2).
APA	Sun, Shaobo.,Che, Tao.,Wang, Jian.,Li, Hongyi.,Hao, Xiaohua.,...&Wang, Jie.(2015).Estimation and analysis of snow water equivalents based on C-band SAR data and field measurements.ARCTIC ANTARCTIC AND ALPINE RESEARCH,47(2).
MLA	Sun, Shaobo,et al."Estimation and analysis of snow water equivalents based on C-band SAR data and field measurements".ARCTIC ANTARCTIC AND ALPINE RESEARCH 47.2(2015).